
public class CircleWithPrivateDataFields {

	private double radius = 1;
	
	private static int numberOfObjects = 0;
	
	public CircleWithPrivateDataFields() {
		numberOfObjects++;
	}
	
	public CircleWithPrivateDataFields(double newRadius) {
		radius = newRadius;
		numberOfObjects++;
	}
	
	public double getRadius() {
		return radius;
	}
	
	public void setRadius(double newRadius) {
		radius = (newRadius >= 0)? newRadius:0;
	}
	
	public static int getNumberOfObjects() {
		return numberOfObjects;
	}
	
	public double getArea() {
		return radius * radius *Math.PI;
	}
	
	
	
}
